Washington — The US Supreme Court on Monday refused to take up multiple appeals examining whether suspected Al Qaeda and Taliban detainees at Guantánamo are being afforded a “meaningful opportunity” to challenge the legality of their open-ended detention.

The high court turned aside appeals filed on behalf of seven Guantánamo detainees. The action came without comment from the justices, but it carried enormous significance.

It lets stand without additional judicial review a series of appeals court rulings since July 2010 that have made it increasingly difficult for Guantánamo detainees to win their cases.

“Today’s decision leaves the fate of detainees in the hands of a hostile [appeals court], which has erected innumerable, unjustified legal obstacles that have made it practically impossible for a detainee to win a habeas case in the trial courts,” said Vincent Warren of the Center for Constitutional Rights, which represents many detainees at Guantánamo.

“The [Supreme Court’s] refusal to get involved at this critical juncture permits the court of appeals to continue to rubber stamp the military’s decision-making,” Mr. Warren said in a statement.

Among the rejected appeals was the case of an alleged recruit from Yemen, Adnan Farhan Abdul Latif.

Mr. Latif’s lawyers complained in their brief to the court that federal appeals court rulings have gutted legal protections at Guantánamo and erected instead a habeas corpus petition process rigged heavily in the government’s favor.

At the center of the appeal was a charge that the appeals court was not faithfully applying a 2008 Supreme Court decision.

That year, the high court ruled for the first time that Guantánamo detainees were entitled to submit habeas corpus petitions directly to federal judges in Washington to determine whether the government had enough evidence to justify their continued open-ended detention without charge.

The 2008 decision, Boumediene v. Bush, said in part: “We do consider it uncontroversial … that the privilege of habeas corpus entitles the prisoner to a meaningful opportunity to demonstrate he is being [unlawfully] held.”

The decision adds: “The habeas court must have sufficient authority to conduct a meaningful review of both the cause for detention and the Executive’s power to detain.”

Following the Boumediene decision, federal judges began closely scrutinizing the quality of evidence offered by the government. Government lawyers started losing cases – until 2010 when the federal appeals court began requiring federal judges to stop submitting the government’s evidence to such rigorous examination.

Instead, the appeals court said judges must embrace a pro-government presumption that the Guantánamo evidence is reliable. Government lawyers had argued that such a presumption was justified because much of the evidence against the detainees was collected under battlefield conditions amid the “fog of war.”

According to a recent study by legal scholars at Seton Hall University School of Law, between 2008 and July 2010 Guantánamo detainees won 56 percent of their habeas challenges. After July 2010, the win rate fell to 8 percent.

That means that prior to July 2010, a federal judge agreed with 19 of 34 detainees claiming there was insufficient evidence to justify their open-ended detention at Guantánamo and ordered their release. After July 2010, a federal judge agreed with only 1 of 12 detainees.

The change is attributed to rulings by the federal appeals court, which has taken up 19 of the Guantánamo habeas cases and reversed or remanded every case in which a federal judge ordered a detainee’s release.

The last detainee to win a release order was Latif, who has been held without charge for 10 years. A federal judge ordered his release from Guantánamo in 2010, but the order was vacated last year by a divided three-judge appeals court panel.

The appeals court told the federal judge in Latif’s case that rather than closely examining and analyzing each piece of evidence, the judge should have viewed the evidence as part of the totality of facts in a light most favorable to the government.

More specifically, the appeals courts required federal judges hearing Guantánamo cases to accord a special presumption of accuracy to US intelligence reports being used to justify continued detention.

Latif’s lawyers said such a special presumption does not comply with the requirements set by the Supreme Court in its Boumediene decision.

“The court of appeals through its actions in this and other cases has created a regime in which Guantánamo habeas cases are becoming exercises in futility,” wrote Washington lawyer S. William Livingston, in his brief on behalf of Latif.

“The entire point of the habeas hearing is to force the government to justify its detention of people who have been neither charged nor convicted, not to allow it to skate by with presumption,” Mr. Livingston said.

Appeals Court Judge David Tatel wrote a dissenting opinion in the Latif case. He said the appeals court’s requirement of a pro-government presumption in favor of US intelligence reports “comes perilously close to suggesting that whatever the government says must be treated as true.”

US Solicitor General Donald Verrilli urged the high court not to take up Latif’s appeal. He said the government had recently located “significant additional evidence” that “tended to support the accuracy of the key report in the record.”

“It would serve little purpose for the [Supreme] Court to review petitioner’s detention on the basis of the record addressed in the decision below and in the petition, without regard to the additional evidence now available to the district court,” Mr. Verrilli wrote in his brief to the court.

Portions of the Latif briefs are classified and have been censored and deleted from public versions of the filings. It is unclear why, given Latif’s decade-long detention, the government was unable until only recently to assemble all relevant evidence against him.

There are currently 169 detainees at Guantánamo. Six have been charged with war crimes and are awaiting trials before a military commission. Many of the rest are slated to be held indefinitely without charge as enemy belligerents. Others may be transferred to their home country for release or continued detention there.

There is no accusation that Latif was involved in terrorism. Instead, the government says he served in 2001 as a soldier for the Taliban on the front lines against the Northern Alliance. Latif and his lawyers dispute this. They say he went to Pakistan and Afghanistan to obtain medical treatment for a lingering head injury from a 1994 car accident.

The case centers around an intelligence report prepared shortly after Latif’s capture in December 2001 that reportedly says Latif admitted his involvement with the Taliban. Government lawyers say the report is accurate and reliable. Latif’s lawyers say the report is a product of shoddy Arabic-English translations and the fog of war. They say there is no corroborating evidence supporting the government’s contention.

As a detainee at Guantánamo, Latif has participated in hunger strikes that necessitated forced feeding. In December 2006, military officials recommended that Latif be transferred from Guantánamo to Yemen for continued detention there by the Yemeni government. That action was never taken.

“The court of appeals has essentially held that a man who has been detained by the government for ten years can be detained for what remains of his life solely on the basis of a few sentences in a single secret intelligence document,” Livingston wrote in his brief.

“This result unreasonably expands the power of the Executive Branch to imprison people without ever charging them or giving them a trial,” he said.